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Pop Rattle Clunk Squeak Knock During Turns Braking Accelerating- keywords accelerate assist bar boards body bracket brake bumps buzz drone exhuast felt frame front heard hop left moan mount mph

Subject:Pop Rattle Clunk Squeak Knock During Turns Braking Accelerating

Models:2007-2008 Chevrolet Silverado
2007-2008 GMC Sierra



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Squeak, Squawk, Pop, Rattle, Clunk, Knock noises have been reported during various driving maneuvers: braking, accelerating, turning, body twist, hitting bumps, etc. Many of these noises have been found to be caused by the installation of aftermarket step assist bars similar to the picture below.


Object Number: 2000497  Size: SH

These aftermarket step assist bars will attach to the body mounts and may contact the frame creating a transfer path for the noise to enter the body. (see picture below)


Object Number: 2000499  Size: SH

Recommendation/Instructions:

If a vehicle comes in for a noise complaint and is equipped with aftermarket step assist bars, before any diagnostic is performed remove the step assist bars.

The Factory/GM Accessory step assist bars DO NOT attached to the body mounts. They mount only to the cab of the truck at the lower rocker panel and currently there have been no known reports from the field of these making noise.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.